Highlights of NAHMS Swine 2000 Part I August 2001
In 2000, USDA’S National Animal Health
Monitoring system (NAHMS) conducted a study of swine operations within the 17
leading pork-producing states.1 These operations
represented nearly 94 percent of the
The following highlights were excerpted from
a report released in July 2001, Swine 2000 Part I: Reference of Swine Health
and Management in the
· For sites with more than 500 breeding females, 85.3 percent of sows were mated via artificial insemination, compared to about 15 percent of sows on sites with less than 250 breeding females.
· Three-fourths (76.4 percent) of sows were mated two or more times per service. For sites with less than 250 breeding females, 64.9 percent of sows and 57.0 percent of gilts were pen-mated.
· For the 40.1 percent of sites that isolated or quarantined new breeding females, over 60 percent tested at least some new breeding females. Of the 65.1 percent isolating new boars, 51.8 percent tested all new breeding males.
· Generally acclimatization measures were adopted more frequently on sites with an inventory of 250 or more. Besides vaccination (used on 84.1 percent of sites), exposure to cull females was used most often (49.0 percent of sites).
· The average litter size was 10.9 pigs, of which 10.0 were born alive and 8.9 survived to weaning. The average preweaning mortality rate was 11.0 percent.
· The most common measure taken for diseases prevention for piglets was to administer iron (75.4 percent of sites). For weaned growing pigs, antibiotics in feed and deworming were the primary treatments (Figure 1).
· Mycoplasma was the most frequently used vaccine in sites with an inventory of 2,000 or more (approximately 60 percent of sites). Over 28 percent of all sites regularly administered vaccines against porcine reproductive and respiratory virus (PRRS).
· During the previous year, 7.6 percent of sites were visited by a state or federal Veterinary Medical Officer (VMO). VMOs visited a higher proportion of larger sites than smaller sites. Over one-third (34.5 percent) of sites had a local practitioner visit at least three times a year.
· About two-thirds of sites restricted entry to the premises to employees only. Of those sites that did not restrict entry, only 23.6 percent required a 24-hour “no-swine-contact” period prior to entry.
· Overall, 56.8 percent of sites allowed trucks to enter site perimeters. Smaller sites were less restrictive than larger sites.
· Baits or poisons were the most frequently used method of rodent control (88.5 percent of sites). Although cats are associated with disease spread, they were nevertheless used for rodent control on 68.0 percent of smaller sites (less than 2,000 total pigs).
· Respiratory disease was the greatest cause of mortality, accounting for 28.9 percent of nursery deaths and 39.1 percent of deaths in grower/finisher pigs.
· Based on death loss data from
· A large percentage of sows were farrowed in total confinement facilities (83.4 percent), and 81.8 percent of pigs were placed in total confinement nurseries.
· Less than 15 percent of pigs were finished in continuous flow facilities.
· The average age of piglets at weaning was 19.3 days. Approximately two-thirds of piglets were weaned from 16 to 20 days of age.
· Many sites (23.9 percent) utilized more than one source to obtain pigs for placement in grower/finisher units.
· Approximately one-third of sites conducted tests on groundwater (37.9 percent) or nutrient content of manure (32.7 percent) during the previous three years. Less than 8 percent tested air quality.
· Nearly one-fourth (23.2 percent) of sites composted dead preweaned pigs.
Burial (37.8 percent of sites) and rendering (45.5 percent) were the most
common methods of carcass disposal for larger pigs.
For more information, contact:
Centers for Epidemiology and Animal
Health USDA:APHIS:VS, attn. NAHMS
2150 Centre Ave., Bldg. B, MS 2E7
Fort Collins, CO 80526-8117